In article <Pine.SOL.3.95.970124142014.29598A-100000@rac1.wam.umd.edu>,
jgruv@wam.umd.edu (joel b gruver) wrote:
> Hello to all,
> I am currently reading an article by E. Skogley of Montana State
> University titled Reinventing Soil Testing for the Future. This article
> was published in SSSA special publication 40, 1994.
>
> In this article Skogley begins by presenting that the current soil
> testing
> "system" is not meeting the needs of farmers and ag industry. He
> presents a graph showing total samples analyzed per year which shows a
> dramatic rise from 1950 to about 65' then a precipitous fall until about
> 1975 then a rise to near maximum levels by 85 and then a drop off
> again... in 1993 1 soil sample was analyzed per 40 ha of crop land...
>
> I can think of a few explanations of this graph...
>
> 1) After a decade + of intensive fertilizer use, soils began testing in
> the high range repeatedly and farmers decided to stop testing...
> 2) Fertilizer prices were high and farm income was low during the 70s
> 3) Soil testing was novel and highly promoted during the 50s and 60s...
>
> Skogley goes on to present that the current extraction based soil testing
> methodologies should be replaced by ion resin technology.
>
> In a nutshell, mixed bed ion exchange resin capsules placed
> incontact with moist soil for approximately 48 hours absorb
> nutrients in a way that mechanistically is much more similar to
> root uptake of nutrients and can be used to provide simpler, cheaper
> and more accurate soil fertility recommendations than current
> methodologies.
>
> Skogley is currently involved with side-by-side tests of ion
> exchange capsules and standard extraction methods. He is also involved
> with marketing ionexchange capsules...
>
> My questions for the list are:
>
> 1) Are farmers and other consumers of soil testing satisfied with the
> current soil testing "system" ?
>
> 2) Do we need to reinvent soil testing ?
>
> 3) Are ionexchange resins the new wave of soil testing that will
> completely replace extraction methodologies ?
>
> I am working on the preliminary stages of a soil quality test based on
> the concept of active carbon being the foundation of soil quality...
>
> 4) What other new soil test methodologies are soon to arrive on the scene
> ?
>
> Joel Gruver
> U of MD, Agronomy
Some comments:
This looks like a really exciting possibility for increasing knowledge
& accuracy of soil testing - as long as the research is correlated with
COMPLETE soil analyses: CEC, base saturation ratios, all major & micro-
nutrients, EC, %OM and even quality of OM (chromotagraphy). Some answers
to your questions:
1) I think there is no one system (although the largest labs in the world,
Harris and A & L Labs all use similiar; partially based on Albrechts
system (although recommendations sometimes ignore his main concepts. The
basic problem is most labs & spit out recommendations, dealers hand them
to farmers (sometimes with their local input); no one tries to get farmers
to understand how soils work.
2) I think we know a lot more than is applied; its made much more
complicated than it really is.
3) I think exchangeable resins, with standard soil tests & plant analysis
would be excellant - with the possible addition of QUALITY of OM tests
(such as Wood's End Lab does) would be as complete as possible.
4) ???
I am presently working on a soil science training manual as my Master's
thesis; it will be to use my 20+ year's testing & field experience in N
California using Albrechts system. I did a survey of 40 N Coast fetilizer
dealers - 1/2 do not even use soil testing; of those who do 1/2 do not
write their own recommendations: Less than 25% of the dealers understand
enough to interpret tests & write recommendations for the growers they
work with!
This manual will explain how to interpret lab analyses & make recs.
Should be very useful for farmers, consultants, researchers, managers,
etc.
It will cover the following components:
*Basic (very) soil science, CEC, base saturation & cation ratios &
history of Albrecht system & why labs have it on their form (but don't use
it) How to calculate lime req. (NOT based on pH), major & micro levels &
needs
*N California fertilizer industry poll & results (use of soil testing)
*Practical problem solving applications using local soils & crops
(tree fruits, wine grapes & others)
*Soil fertility & pest & disease interactions - from the literature
and my experience with local crops ( a favorite subject of mine)
*QUALITY crop production using soil fertilityas the base
*A proposed classification system based on ALbrecht's principles
which would overlay the USDA SCS soil surveys (could be used anywhere) and
provide the information you REALLY need: basic mineral content & balance,
limiting factors for crop production, average amount of amendments needed
in a soil type, problem soils & solutions, why soils are the way they are.
*Mostly dealing with "neutral" (below pH 8.3) and acid soils; the
system works an all soils - perhaps a second addition for arid soils.
I am considering posting the chapters as I write this; several are
already close to finished. I would gladly do so if:
-I can figure out how - I'm not that good with news groups yet
-Proper credit is given to those who quote/use info
-Writings will be critiqued intelligently; I'm very interested in
usefulness, practicality, universal application, & field experiences of
others, practical applications, etc.
Gregg Young, CPAg
gyoung@pacific.net
--
Sustainable agriculture in Northern California since 1973